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Purifi 1ET6525SA, Orchard Starkrimson 25 or? for high pass amp

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I got a Devialet D250Pro many years ago mostly because it has a built in digital crossover option. I am crossing over around 140 to 200Hz and using an amp built from Hypex Nilai 500 modules for the low pass driving my woofers. A significant issue I have with Devialet crossover function is that their curves are not correct: the slopes are more shallow than the crossover order should (4th looks more like 16dB per octave) but more significantly it has an additional shallow slope at least 2 octaves before /after the crossover frequency. I just testing some analog active crossover kit from Xkitz (Linkewitz 24dB/octave) and the slopes are much closer to what one should except.
So I am thinking of getting a great dac and using this (or maybe there are even better ones) analog active crossover. The Nilai based amps are great for low frequencies but their behavior is less stellar at high frequencies as are the high power class D amps. The power requirements for the high pass (especially considering that there are no passive crossover elements waisting energy) are quite low.
Purify released recently an improved lower power module1ET6525SA but I have not seen any testing except their own data sheet https://purifi-audio.com/shop/1et65...,8197,8637,8199,8597,8638,8202,8203,8204,8205
GaN based class D amps have a higher switching frequencies which should theoretically improve high frequency performance but a lot of these are designed to mimic tube amps but I think the Orchard audio is likely not in that camp.They just came up with an improve version of their 150W module https://orchardaudio.com/shop/starkrimson-25-amplifier-module/ but I found no tests for that specific unit.
I would appreciate any comments about these amps or suggestion to alternatives for my specific requirements
 
Distortion is much higher at 10kHz or higher. I had an early generation of Hypex module and also a Kharma MP150, a Putzeys designed amp. These earlier generation of class D were sound wise not great at high frequencies, one reason I kept a Pass Labs amp and later got the Devialet. The Nilai is a significant improvement but the most recent Purify amps bettered them. Besides I don't need 500W
 
FAQ #7 and #8:

TBH I would keep the Devialet and be happy.
 
Distortion is much higher at 10kHz or higher.
The 1st harmonic of 10kHz is 20kHz. ;) And, I'd be shocked if the distortion is worse than 1%.

IMD is possible, but likely not audible either.


...I've NEVER heard ANY distortion from ANYTHING that wasn't broken or over-driven. (Except maybe analog records which might not qualify as "broken"). But, I don't claim to have golden ears. I just consider myself an audio lover and a "picky listener". ;)


The power requirements for the high pass (especially considering that there are no passive crossover elements waisting energy) are quite low.
The power requirements for higher frequencies are lower, but there is virtually no loss in the high-pass section of a passive crossover. (Except sometimes it's designed-in intentionally if the tweeter is more sensitive than the midrange or woofer.) Plus, it's "good practice" to put a capacitor in series anyway so that higher-power lower-frequencies don't get accidently fed-into the tweeter.

There is SOME loss through the inductors in the woofer & midrange section but it's insignificant compared to a change in amplifier power.

There are other reasons for using an active crossover...
 
The Starkrimson will have lower distortion in the highs with increased power. Hypex and Purifi amps have very low distortion with 1W but the distortion increases above 5KHz with more output.

Whether this is audible or not, may depend on how much power is drawn from the speakers.
 
The power requirements for higher frequencies are lower, but there is virtually no loss in the high-pass section of a passive crossover. (Except sometimes it's designed-in intentionally if the tweeter is more sensitive than the midrange or woofer.) Plus, it's "good practice" to put a capacitor in series anyway so that higher-power lower-frequencies don't get accidently fed-into the tweeter.

There is SOME loss through the inductors in the woofer & midrange section but it's insignificant compared to a change in amplifier power.

There are other reasons for using an active crossover...
You assuming a standard crossover. I am not using a tweeter but an almost full range driver. Inductor and capacitors get more problematic (especially price wise) the lower the crossover frequency and 4th order with passive is rarely achieved. I stopped using passive crossover around 20 years ago
 
[Grok 3] Increasing the switching frequency from 800 kHz to 1.1 MHz in the Starkrimson 25 compared to the original Starkrimson has several implications for both technical performance and sound quality. Below, I outline the main consequences, based on class D amplifier engineering principles and the context provided...
-> https://x.com/i/grok/share/VGX12NitaDU7iguW7cn2q03wd

View attachment 449683

Joey G's Audio Channel: The Show/Lone Star Audiofest 2025 - My 1st Class D Seminar <- transcription


Orchard Audio: Starkrimson 25 module

View attachment 449685
what BS from AI.
 
While we are being more tolerant of AI content, repetitive posting of AI content without context is spamming.

Offending posts have been deleted.
 
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